Citation

Lee JF, Brown SR, Lange AP, Brothers RM. J. Strength Cond. Res. 2013; 27(12): 3402-3411.

Affiliation

Environmental and Autonomic Physiology Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin.

Copyright

(Copyright © 2013, National Strength and Conditioning Association)

DOI

10.1519/JSC.0b013e318291b29f

PMID

23539083

Abstract

Non-vented "aerodynamic-helmets" reduce wind resistance but may increase head (Th) and gastro-intestinal (Tgi) temperature, and reduce performance when worn in hot conditions. This study tested the hypothesis that Th and Tgi would be greater during low intensity cycling in the heat while wearing an aero-helmet (AERO) vs. a traditional vented racing-helmet (REG). This study also tested the hypothesis that Th, Tgi, and finish time would be greater, and power output would be reduced during a self-paced time trial in the heat with AERO vs. REG. Ten highly-trained, heat-acclimated endurance athletes conducted low intensity cycling (50%v[Combining Dot Above]O2max; LIC), and a high intensity 12-km self-paced time trial (12-km TT) on a cycle ergometer in 39°C on 2 different days (AERO and REG), separated by >48hrs. During LIC, Th was higher at min 7.5 and all time points thereafter in AERO vs. REG (P<0.05). Similarly, during the 12-km TT Th was higher at min 12.5, 15, 17.5 in AERO vs. REG (P<0.05). Heart rate (HR) and Tgi increased during LIC, and during 12-km TT (both P<0.001); however, no significant interaction (helmet X time) existed for HR or Tgi at either intensity (all P>0.05). No group differences existed for finish time or power output during the 12-km TT (both P>0.05). In conclusion, Th becomes elevated during cycling in the heat with an aero-helmet compared to a traditional vented racing helmet during low and high intensity cycling, yet Tgi and HR responses are similar irrespective of helmet type and Th. Furthermore, the higher Th that develops when an aero-helmet is worn during cycling in the heat does not affect power output or cycling performance during short duration, high intensity events.

Language: en